Abstract: The present invention is all error detection and correction scheme that enables the use of Horner's algorithm for the computation of EDC syndromes from the computed error pattern. Specifically, “transformed” EDC syndromes are computed during the read back of data and parity from the medium. The transformed syndromes are values of the polynomial whose coefficients occur in reverse order from that of the EDC codeword polynomial. In essence, by reversing the order of the coefficients, the Chien search processes the terms in descending order which is the right direction for Horner evaluation.

Abstract: The present invention is all error detection and correction scheme that enables the use of Horner's algorithm for the computation of EDC syndromes from the computed error pattern. Specifically, “transformed” EDC syndromes are computed during the read back of data and parity from the medium. The transformed syndromes are values of the polynomial whose coefficients occur in reverse order from that of the EDC codeword polynomial. In essence, by reversing the order of the coefficients, the Chien search processes the terms in descending order which is the right direction for Horner evaluation.

Abstract: The present invention is an error detection and correction scheme that enables the use of Horner's algorithm for the computation of EDC syndromes from the computed error pattern. Specifically, “transformed” EDC syndromes are computed during the read back of data and parity from the medium. The transformed syndromes are values of the polynomial whose coefficients occur in reverse order from that of the EDC codeword polynomial. In essence, by reversing the order of the coefficients, the Chien search processes the terms in descending order which is the right direction for Horner evaluation.

Abstract: The present invention is an error detection and correction scheme that enables the use of Horner's algorithm for the computation of EDC syndromes from the computed error pattern. Specifically, “transformed” EDC syndromes are computed during the read back of data and parity from the medium. The transformed syndromes are values of the polynomial whose coefficients occur in reverse order from that of the EDC codeword polynomial. In essence, by reversing the order of the coefficients, the Chien search processes the terms in descending order which is the right direction for Horner evaluation.

Abstract: The present invention is an error detection and correction scheme that enables the use of Horner's algorithm for the computation of EDC syndromes from the computed error pattern. Specifically, “transformed” EDC syndromes are computed during the read back of data and parity from the medium. The transformed syndromes are values of the polynomial whose coefficients occur in reverse order from that of the EDC codeword polynomial. In essence, by reversing the order of the coefficients, the Chien search processes the terms in descending order which is the right direction for Horner evaluation.

Abstract: An error correction and miscorrection detection apparatus includes a memory buffer for storing user data contained in a data signal. A syndrome computer circuit generates a plurality of EDC syndromes form an EDC codeword. The EDC codeword includes user data encoded with a plurality of m-bit EDC parity symbols. The EDC codeword is encoded with plurality of n-bit ECC parity symbols to form the data signal, such that m>n. An ECC error correction circuit corrects the user data with an error signal generated for each corruption of the data signal. A completion is signal generated once correction of the EDC codeword is complete. A syndrome fix-up circuit is configured to adjust the EDC syndromes based on the received error signals. Once the completion signal is received, a miscorrection by the ECC error correction circuit is detected if a value of the adjusted syndromes is not equal to zero.

Abstract: Herein is disclosed a method and apparatus for controlling power consumption of a disc drive in a portable computer based upon statistical characteristics of recent user disc access. This is accomplished by a disc drive that initially instantiates a set of thresholds, each of which govern transition into a corresponding power consumption mode. Next, the disc drive measures, at intervals, the time span since the disc drive was last issued a command. Prior to receipt of a new command by the disc drive, the disc drive is progressively transitioned into lower power consumption modes as the measured time span since the last command was issued meets each successive threshold. Following receipt of a new command by the disc drive, the threshold governing transition in to the next lower power consumption mode is adjusted based upon the measured time span.

Abstract: The present invention pertains to a method for determining if data read from a storage medium has been read from physical block address (PBA) other than the expected PBA. Data that is stored on the data storage medium is encoded in accordance with a protocol that includes randomizing the data and combining the first k.times.2t bytes of the data with a PBA string, where t is the error correction capacity associated with the error correction technique used in the data storage system and k is the number of bytes of the PBA that are used in the PBA string. In addition, the data is k-way interleaved with parity data appended to it. When the data is read from the data storage medium, the data is decoded using a scheme corresponding to the encoding protocol. If errors are present in the data and exceed the error correction capacity, the first 2t bytes of each interleave are marked as erasures and a second correction is performed by an error correction unit.